L-arginine is an amino acid classified as essential with respect to its growth effect in rats. The amino acid is also useful inter alia as a starting compound in the preparation of arginine glutamate which is an adjunct in management of ammonium intoxication due to hepatic failure.
Heretofore, L-arginine has been prepared using various methods. For example the L-form has been obtained by hydrolysis of proteins. In industrial practice it is precipitated from gelatine hydrolyzate as the flavianate.
As for processes for the production of L-arginine by fermentation using a microorganism of the genus Bacillus, processes using strains which are resistant to arginine analogues are known as described in Applied Microbiology Vol. 32, P. 987 (1971) and Japanese Patent Publication No. 25359/74. Further, as for the production of L-arginine by a microorganism having a nutritional requirement, Japanese Unexamined Patent Application published under No. 61388/74 discloses the production of L-arginine by a strain of the genus Brevibacterium having a requirement for guanine.
However, natural processes which have a high yield of L-arginine are in demand for utilization in industrial practice. To this end, it has been found that improved yields of L-arginine may be attained by fermenting certain auxotrophic mutants of the genus Bacillus.